Summary with the recent advances in high-throughput genomic and proteomic technologies, there is an urgent demand and shortage of the next-generation PhD biostatisticians who understand biology, especially genetics and genomics because they are so essential in understanding mechanisms and risk of disease, and how people respond to different therapeutic interventions. However, traditional training in biostatistics, which emphasizes almost exclusively on statistical theory and methods, no longer meets the need. As a response, this application develops an innovative and interdisciplinary pre- doctoral T32 Biostatistics in Genetics and Genomics (BiG2) training program and request support for implementing it. The primary mission of this training grant is to prepare Biostatistics predoctoral trainees for leadership roles in biomedical and public health research through excellent training and mentorship in genetics and genomics. Our specific objectives include completion by each trainee of required and elective coursework in our PhD program and in other departments, mentored learning through interdisciplinary research projects, development of communication and networking skills, attendance at and participation in journal clubs and seminars, and successful completion of a program of interdisciplinary research through their dissertation, all of which give our trainees broad training in a rapidly expanding field. The distinctive feature of the proposed training program is that each objective has both a biostatistical aspect and a biomedical aspect. A key is to ensure each trainee learns how to carry out a cohesive and interdisciplinary research program, including working with biomedical researchers, and writing, submitting, editing, and resubmitting scholarly papers. The program is designed to support students for up to three years at the early stages of their PhD studies, after which their support will switch to projects funded by the faculty mentors' research grants. We request salary, tuition, and limited travel support for 1 new predoctoral trainee in each of the fist two years of a 5-year funding period, and for 2 new predoctoral trainees in each of the following three years. This training program will contribute to our nation's ability to analyze important biomedical data, thus improving the health and well-being of the public in the long run.